We are at the student astronautics competition: 'Eternal challenge'. Lucy had just shot off her rocket, and we are walking past the stalls. There are wireless airplanes hanging on wires, there are robots, and there is face painting.

I sit down with Lucy at the face painting table. "What will you have?" the guy at the table asks me.

"Oh, you do adults?"

"Of course." He thinks a bit, "But nothing too naughty."